The present invention relates to an elastomer valve and, in particular, to a one-way, bi-leaflet (e.g. duck-bill shaped) valve assembly that mounts to liquid conduits, such as flow ports located below other elevated system conduits or a reservoir and from which it is periodically necessary to clear latent fluid (e.g. when winterizing water lines for swimming pools, recreation vehicles and vacation properties).
Numerous one way valve devices are known for use in wide varieties of plumbing applications and systems. The present valve assembly in one construction is used to facilitate and overcome problems encountered when winterizing swimming pools.
Winterizing swimming pool plumbing lines typically requires the draining of the pool water below the level of the return openings, such as at the skimmers or pool sidewalls, to assure that no water enters or backs-up into the lines as they are seasonally drained, filled with anti-freeze and/or plugged. Such drainage wastes water and treatment chemicals. Reduced water levels can also produce cover damage such as where the pool has an automatic covering system.
For systems where the water level is not reduced, plugs can be added to the submerged ports as air is blown through the ports, but which can be unpleasant due to the attendant splashing that occurs as the plugs are inserted.
One valve that can be added to conduits that require seasonal clearing is disclosed at U.S. Pat. No. 6,877,524 and application publication US2004/0177882 to Vasilev. The valve of the subject invention can also be used in the foregoing applications and others where a one-way flow valve is desired. The valve finds particular application at submerged ports to permit expelling latent liquid and prevent backflow from low pressure surrounding water.
In one preferred form, the valve provides a support fitting having a suitable fastener coupling (e.g. threaded or adhesive) that mounts to an associated conduit. An elastomer duck-bill shaped valve piece mounts in the fitting. The valve piece is shaped to promote a flexing when mounted to the fitting to induce provided leaflets into abutting engagement in a closed condition, except when liquid or air is expelled from the conduit. Under forward pressure, the valve piece flexes open. Otherwise, the leaflets are constructed to resiliently close upon themselves with the release of pressure to maintain a flexible aperture in a closed condition to resist counter flow. A cap that mates with the fitting is provided as a cover to the valve piece to further assure against reverse flow.